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21.
In a group of 84 pairs of 11-year-old children of both sexes, the level of the alpha1-antitrypsin (alpha1-AT) were ascertained in the autumn and spring. Although the mean levels of alpha1-AT in the two seasons hardly differed, the highly significant seasonal changes in the distribution curves of alpha1-AT values were noted in boys, whereas the levels showed higher stability in girls. 相似文献
22.
We examined optimal temperatures for growth and the upper thermal tolerance of juvenile northern leatherside chub ( Lepidomeda copei ). We conducted 2 experiments using the acclimated chronic-exposure method to estimate optimal temperature for growth of age-0 northern leatherside chub (range 12.8–28.3 °C). Upper thermal tolerance was estimated using the critical thermal maximum (CTM) and upper incipient lethal temperature (UILT) methods for fish acclimated at 15, 18, 23, and 28 °C. We also measured stream temperatures in Yellow Creek, Summit County, Utah, during July–August 2006 to compare our results to actual summer stream temperatures. Survival in growth tests was not significantly different between treatment temperatures in either experiment (P > 0.098). The optimal temperature for growth in the 1st trial estimated from the 2nd-order polynomial regression was 23.0 °C, falling outside the range of experimental temperatures (12.8–22.2 °C). The estimated optimal temperature for growth in the 2nd trial was 23.2 °C. In the upper thermal tolerance tests, juvenile northern leatherside chub had CTM values between 29.6 and 35.0 °C; CTM values increased as acclimation temperature increased. Upper incipient lethal temperatures (LT50) ranged from 26.5 to 30.2 °C, increasing with acclimation temperature. Summer stream temperatures in Yellow Creek had a lower mean (14.0–18.1 °C) than did the optimal temperature for growth determined in these studies, but these temperatures exhibited diel fluctuations as large as 15.7 °C. 相似文献
23.
The influence of current year foliage age on food consumption and utilization by the western spruce budworm, Choristoneura occidentalis (Lepidoptera:Tortricidae), was examined. Larvae were fed immature foliage of Douglas-fir ( Pseudotsuga menziesii var. glauca ), Engelmann spruce ( Picea engelmannii ), and corkbark fir ( Abies lasiocarpa var. arizonica ) in June and August of 1981 and Douglas fir in June and July of 1982. All larvae feeding on early season (June) foliage reached maturity. Larvae feeding on middle (July) and late (August) season foliage died before reaching pupation. Relative growth rate and efficiency of conversion of ingested food decreased with foliage age in both the 1981 and 1982 experiments. Relative consumption rate increased with foliage age in the 1981 and decreased in the 1982 experiment. 相似文献
24.
Retinoblastoma. A transcriptional tryst 总被引:12,自引:0,他引:12
25.
D. Reinhardt J. Wagner H. J. Schümann 《Cellular and molecular life sciences : CMLS》1973,29(7):830-832
Zusammenfassung Am Kaninchen-Ileum besteht die durch Temperaturerhöhung bedingte Rechtsverschiebung der Dosis-Wirkungs-Kurven von Isoprenalin und Th 1165a aus einem reversiblen und einem irreversiblen Anteil. 相似文献
26.
I. Palik M. Zs. Koltai M. Wagner I. Kolonics G. Pogátsa 《Cellular and molecular life sciences : CMLS》1982,38(8):934-935
Summary The conductivity of the coronary arterial bed increased in healthy and decreased in alloxan-diabetic dogs in response to intracoronary administration of norepinephrine or sympathetic stimulation. This suggests a modification of adrenergic receptors sensitivity in diabetes. 相似文献
27.
Scanning immunoelectron microscopy of mouse B and T lymphocytes 总被引:5,自引:0,他引:5
28.
29.
The tropics have been suggested as the drivers of global ocean and atmosphere circulation and biogeochemical cycling during the extreme warmth of the Cretaceous period; but the links between orbital forcing, freshwater runoff and the biogeochemistry of continental margins in extreme greenhouse conditions are not fully understood. Here we present Cretaceous records of geochemical tracers for freshwater runoff obtained from a sediment core off the Ivory Coast that indicate that alternating periods of arid and humid African climate were driven by orbital precession. Our simulations of the precession-driven patterns of river discharge with a global climate model suggest that ocean anoxia and black shale sedimentation were directly caused by high river discharge, and occurred specifically when the northern equinox coincided with perihelion (the minimum distance between the Sun and the Earth). We conclude that, in a warm climate, the oceans off tropical continental margins respond rapidly and sensitively to even modest changes in river discharge. 相似文献
30.
V. Figarová J. Presl V. Wagner J. Horský 《Cellular and molecular life sciences : CMLS》1970,26(9):1017-1018
Zusammenfassung Die Einlagerung von131I-HCG und131I-Serumalbumin in einige Organe unreifer Rattenweibchen wurde gammaradiometrisch gemessen. Eine signifikant erhöhte Akkumulation der Radioaktivität nach131I-HCG-Verabreichung wurde im Ovarium, dem Uterus, der Hypophyse und der Schilddrüse festgestellt. 相似文献